Trait HasTag 

#[doc(hidden)]
pub unsafe trait HasTag {
    type Tag: Immutable;
    type ProjectToTag: Project<Self, Self::Tag>;

    // Required method
    fn only_derive_is_allowed_to_implement_this_trait()
       where Self: Sized;
}

Safety

Self::ProjectToTag must satisfy its safety invariant.

Required Associated Types

type Tag: Immutable

The type’s enum tag, or () for non-enum types.

type ProjectToTag: Project<Self, Self::Tag>

A pointer projection from Self to its tag.

Safety

It must be the case that, for all slf: Ptr<'_, Self, I>, it is sound to project from slf to Ptr<'_, Self::Tag, I> using this projection.

Required Methods

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<A> HasTag for (A,)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B> HasTag for (A, B)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C> HasTag for (A, B, C)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D> HasTag for (A, B, C, D)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E> HasTag for (A, B, C, D, E)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F> HasTag for (A, B, C, D, E, F)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G> HasTag for (A, B, C, D, E, F, G)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H> HasTag for (A, B, C, D, E, F, G, H)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I> HasTag for (A, B, C, D, E, F, G, H, I)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J> HasTag for (A, B, C, D, E, F, G, H, I, J)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K> HasTag for (A, B, C, D, E, F, G, H, I, J, K)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

impl<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z> HasTag for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z)

type Tag = ()

type ProjectToTag = CastToUnit

fn only_derive_is_allowed_to_implement_this_trait()

where Self: Sized,

Implementors

impl<T: ?Sized> HasTag for ManuallyDrop<T>

type Tag = ()

type ProjectToTag = CastToUnit